Comprehensive Tank Cleaning, Blasting & Recoating Services for a Large Motor Yacht in South Florida
Overview
Coastal Tank recently completed a full-service tank restoration project aboard a large motor yacht undergoing maintenance at a South Florida shipyard. This multi-phase job included the cleaning, abrasive blasting, metal repair, and complete recoating of a mixed-service waste tank. The work spanned several weeks and required extensive coordination, interior protection, safety measures, and precision execution to restore the tank to optimal condition.
Project Summary
The onboard tank, used for combined black/grey water service and holding over 3,400 gallons, required a complete refurbishment due to widespread coating failure and corrosion. Coastal Tank mobilized a trained crew, full PPE, high-capacity pressure cleaning equipment, a diesel-powered blasting system, and a 1,300 CFM industrial vacuum to perform the work in compliance with all safety and environmental requirements.
3 Phase Approach
Phase 1: Cleaning & Initial Inspection
The project began with full mobilization to the vessel, interior protection along hose routes, and setup of all equipment. After pumping out residual contents, the tank underwent a hot-water pressure cleaning, removal of debris, and vacuuming to bare metal.
During this process, technicians removed a significant volume of loose rust scale and solid waste—17 bags of debris—before preparing the space for inspection.
Inspection revealed:
- Widespread coating failure across the tank interior.
- Bare metal exposure throughout.
- Severe corrosion, including pitting, metal loss, and deterioration on internal structures.
- A corroded-through hole along an upper section of the tank wall, requiring structural repair.
These findings made it clear that spot repairs would not be sufficient; a full abrasive blast and coating replacement were necessary
Phase 2: Abrasive Blasting & Metal Repairs
Before blasting began, the tank was pressure washed again using a salt-removal solution to prevent contamination during surface preparation. Crew members sealed and protected all pipe penetrations and interior areas to keep the vessel clean throughout the process.
The team then abrasively blasted the entire tank interior to SSPC-SP 10 / NACE No. 2 “Near White Metal,” achieving an average surface profile of 3.3 mils, well within specification. After blasting, shipyard personnel performed steel repairs, which were then brush-blasted again to ensure proper adhesion for the upcoming coating system.
Soluble salt testing was conducted and confirmed to be within acceptable ranges.
Phase 3: Belzona Repair & Epoxy Coating Application
After steel preparation:
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Extensive pitted areas were rebuilt using Belzona 1111 metal repair compound.
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All edges, welds, and angular surfaces were stripe-coated with high-performance Sherwin Williams Novaplate 360 to ensure full protective coverage.
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Environmental conditions—surface temperature, dew point, ambient humidity—were recorded and confirmed suitable before each coating cycle.
The tank then received:
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Two spray-applied coats of Novaplate 360 at 10–15 mils per coat.
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Final dry film thickness readings averaging 23–35 mils, meeting the recommended protective range.
Scope of Work
The completed work resulted in:
- A fully rehabilitated tank interior meeting high-performance marine coating standards.
- Structural reinforcement of previously corroded and wasted areas.
- A durable epoxy lining designed for long-term resistance to waste, moisture, and chemical exposure.
- Full documentation, including photo records, inspection notes, surface testing results, and coating data.
Results
This project showcases Coastal Tank’s ability to handle complex, large-scale tank restoration work with precision, safety, and attention to detail, from initial cleaning through final coating cure.